Management of Commercially Generated Radioactive Waste - U.S. ...

62
CONSEQUENCE ANALYSIS
Risk defined as the product of probability times consequences should be qualified to
reflect the possibility of increased public concern where serious consequences are involved.
(219)
Response
While risk assessments are not limited to worst cases, only cases believed to be
"worst" were analyzed in the Statement. In its presentation, the Statement first outlines
the radiological impacts of unintended events from a consequence viewpoint. The frequency
of occurrence of the particular event is then identified so that if one desires to determine
the expected impact from such an event one may do so. However, the consequences of a given
event (in the absence of the frequency of occurence) are certainly an upper bound estimate
of the impacts.
Draft p. 1.17
Issue
The difference between "major disasters" and "primary events" is unclear. (34,
208-NRC, 218-DOI)
Response
The breach of a repository by a major disaster has two sources of environmental damage.
The first is due to the physical disruption of the landscape by the primary event; for exam-
ple, crater formation in a meteorite impact or a nuclear weapons strike. A second source
of damage is the radiological consequences of a release of radionuclides to the environment.
For all disasters considered in this Statement except solution mining, the consequences of
radionuclide releases are less than those of the initiating natural disaster.
Draft p. 1.17
Issue
One commenter noted that the uncertainty of geologic prediction does limit the applica-
tion of risk assessment. If the probability of a certain geologic event occurring is not
known, how can a reliable risk assessment be calculated to include the potential impact of
such an event. (218-DOI)
Response
DOE agrees. However, if the consequences remain insignificant over many orders of mag-
nitude, then the uncertainty may not be important.